Weird Situation - ???

[Cornellref]

A1 tries to rebound A2's shot but trips and falls to the ground. He is sitting with his butt out of bounds and the ball is rolling towards him in the key area. Then A1 intentionally kicks the ball. His leg is in bounds but the rest of him is out. Here's the question: Is this a kick ball or since he is mostly out of play an out-of-bounds violation? Either way its a turnover but I want to know the correct call. Post your thoughts, thanks.